1. Field of the Invention
The present invention relates to a heat resistant sheath for endoscope, configured to guide an insertion portion of an endoscope apparatus, and an endoscope system provided with the heat resistant sheath for endoscope.
2. Description of the Related Art
Conventionally, endoscope apparatuses including an insertion portion which may be inserted into an object and which enables observation of the object that an observer cannot directly see by eye are being used. According to such an endoscope apparatus, at the time of insertion of the insertion portion into the object, an endoscope guide tube is sometimes externally attached to the insertion portion to guide the insertion portion.
With respect to such an endoscope guide tube, a technique is known, as disclosed in Japanese Patent Application Laid-Open Publication No 2010-26391, for example, according to which a heat resistant sheath into which an insertion portion is inserted to observe a high temperature environment is included, and cooling air is made to flow inside the heat resistant sheath so as to protect the insertion portion in the high temperature environment.